NAIROBI, Kenya — A military plane carrying politicians to a peace conference crashed while attempting to land in northern Kenya during bad weather Monday, killing at least 14 people, including two assistant Cabinet ministers.

President Mwai Kibaki declared three days of national mourning.

Four of the 17 people on the plane were pulled from the fiery wreckage alive and flown to Nairobi for treatment, witnesses said. But one survivor died on the way.

The plane crashed into a hill near Marsabit, 280 miles northeast of Nairobi. The politicians on board were heading to a conference intended to ease tribal tensions along the Ethiopian border, Parliamentary Speaker Francis ole Kaparo told a news conference.

“This is the worst tragedy to hit the National Assembly,” Kaparo said with tears in his eyes. “We have lost a lot of very good people in this crash.”

He said Minister for Youth Affairs Mohammed Kuti was among the dead, but Minister for Foreign Affairs Raphael Tuju and government spokesman Alfred Mutua insisted that Kuti was not on the plane.

Both men said the other victims included Assistant Minister for Internal Security Mirugi Kariuki; Assistant Minister for Regional Development Authorities Titus Ngoyoni; and the deputy leader of the opposition KANU party, Bonaya Godana.

Another passenger was Abdullahi Adan, a Kenyan member of the East African Legislative Assembly and a retired army general under President Daniel arap Moi, Kaparo added. The East African Legislative Assembly includes lawmakers from Kenya, Tanzania and Uganda.

“Initial investigative reports of the Marsabit air crash indicate that the Y-12 military airplane may have crashed due to poor visibility caused by bad weather,” Mutua said in a statement.

Police also said the crash appeared to be an accident.

In July, unknown assailants killed scores of people in Marsabit, including at least two dozen children in a school, provoking retaliatory attacks between members of different tribes and raising tensions along the border with Ethiopia.

Since then, there have been efforts to ease tensions.

In January 2003, a plane carrying four Cabinet ministers crashed in western Kenya, killing one minister and the two pilots. A public inquiry into the crash recommended no more than three Cabinet ministers or senior government officials should travel on the same flight for security reasons.

The report also said many airstrips in the country were poorly maintained and the government did not allocate enough money for repair and maintenance.